[P006] Poster

1:00 PM - 1:50 PM JST(4:00 AM - 4:50 AM UTC)

[P03-320] Genome-Integrated Multi-Output Genetic Circuit with Serine Recombinase-Based Output Switching

○Toshiki Saito¹, Koko Nakata², Shunsuke Takahashi³ (1. Materials and Life Sci., Grad. Sch. Adv. Sci. Technol., Tokyo Denki Univ. (Japan), 2. Div. Life Sci. Eng., Grad.Sch. Sci. Eng., Tokyo Denki Univ. (Japan), 3. Div. Life Sci., Sch. Sci. Eng., Tokyo Denki Univ. (Japan))

Keywords:

Genetic circuit,Gene Expression Regulation,logic gate,Recombinase

Synthetic genetic circuits enable programmed information processing in living cells and hold broad potential in biosensing, biomanufacturing, and cellular control. However, in conventional designs, altering output behavior typically requires a complete redesign of the circuit architecture, thereby limiting modularity and reusability. To address this limitation, we constructed a multi-output genetic circuit system that combines genome-integrated serine recombinase expression modules with plasmid-based logic and output modules, thereby enabling output switching through site-specific DNA excision.Genetic circuits were first designed using Cello-v3-core, and their logic functions were experimentally validated in Escherichia coli DH10b. We then investigated whether serine recombinases could switch circuit outputs by excising a transcriptional terminator located upstream of an eYFP reporter on a plasmid. To characterize the factors influencing excision efficiency, attB and attP sequences were systematically varied, and eYFP expression was measured as a readout of terminator removal. For a broader comparison of recombinase performance, six integrases were each expressed under the control of four different inducible promoters in genome-integrated expression modules, and excision efficiencies were evaluated under both induced and uninduced conditions.Recombinase modules exhibiting high excision efficiency were selected and integrated into the genetic circuit system to assess whether the input–output relationship could be reconfigured without modifying the upstream logic module. To demonstrate the concept, we successfully demonstrated output switching from an OR to a NOR gate. Taken together, these results show that genome-integrated serine recombinase expression modules offer an effective strategy for output switching in plasmid-based genetic circuits and may contribute to the development of more modular and reconfigurable synthetic biology platforms.